Studi Eksperimental Pengaruh Passive Damper Dengan Material Brass Untuk Daerah Stabil Pada Proses Finishing Boring Bar

Cahya, Reynaldi Dwi and UNSPECIFIED (2026) Studi Eksperimental Pengaruh Passive Damper Dengan Material Brass Untuk Daerah Stabil Pada Proses Finishing Boring Bar. Other thesis, Institut Teknologi Sepuluh Nopember.

Text 5007221004-Undergraduate_Thesis.pdf - Accepted Version Restricted to Registered users only Download (4MB) | Request a copy

Abstract

Proses boring merupakan salah satu proses pemesinan yang penting untuk menghasilkan komponen dengan tingkat akurasi dan kualitas permukaan tinggi. Namun, proses ini sering menghadapi permasalahan chatter vibration atau getaran berlebih yang menyebabkan penurunan kualitas permukaan, ketidaktepatan dimensi, serta mempercepat keausan alat potong. Salah satu upaya yang dapat dilakukan untuk mengatasi permasalahan tersebut adalah dengan menambahkan Dynamic Vibration Absorber (DVA) pada boring bar guna meredam getaran yang terjadi selama proses pemotongan. Penelitian dilakukan secara eksperimental menggunakan boring bar berbahan AISI 4140 yang dipasangi passive damper berbahan brass dengan panjang 96 mm (60% overhang). Variasi parameter pemotongan yang digunakan meliputi kecepatan putaran spindle sebesar 630 rpm, 920 rpm, dan 1250 rpm, serta depth of cut sebesar 0,1 mm, 0,3 mm, dan 0,5 mm, dengan feed rate konstan sebesar 0,05 mm/rev. Respon getaran diukur menggunakan accelerometer dan PicoScope, kemudian data diolah menggunakan MATLAB melalui proses filtering dan smoothing untuk memperoleh nilai Root Mean Square (RMS). Selanjutnya dilakukan pemetaan stability map untuk menentukan kondisi stabil dan tidak stabil pada setiap variasi parameter pemotongan. Hasil penelitian menunjukkan bahwa penggunaan passive damper berbahan brass mampu meningkatkan kestabilan proses pemesinan dengan menurunkan respon getaran pada beberapa variasi parameter pemotongan. Nilai RMS terendah diperoleh pada variasi A1 (630 rpm dan depth of cut 0,1 mm), yaitu sebesar 0,281 m/s² pada sumbu-X dan 0,456 m/s² pada sumbu-Y, sehingga ditetapkan sebagai kondisi pemesinan paling stabil. Sebaliknya, nilai RMS tertinggi diperoleh pada variasi A6 (920 rpm dan depth of cut 0,5 mm), yaitu sebesar 2,386 m/s² pada sumbu-X dan 3,749 m/s² pada sumbu-Y, yang menunjukkan kecenderungan terbesar mengalami chatter. Berdasarkan stability map, daerah stabil diperoleh pada variasi A1, A4, A7, dan A8, sedangkan variasi A2, A3, A5, A6, dan A9 berada pada daerah tidak stabil. Hasil pengamatan permukaan benda kerja juga menunjukkan bahwa variasi yang berada pada daerah stabil menghasilkan kualitas permukaan yang lebih halus dan homogen dibandingkan variasi pada daerah tidak stabil.
=======================================================================================================================================
The boring process is one of the important machining processes to produce components with a high level of accuracy and surface quality. However, this process often faces problems with chatter vibration or excessive vibration that causes a decrease in surface quality, dimensional inaccuracy, and accelerates cutting tool wear. One effort that can be done to overcome these problems is by adding a Dynamic Vibration Absorber (DVA) to the boring bar to dampen vibrations that occur during the cutting process. This study aims to analyze the effect of using DVA on the vibration response of the bor ing bar and determine the stability region in the boring process. The study was conducted experimentally using an AISI 4140 boring bar equipped with a 96 mm (60% overhang) brass passive damper. The machining parameters consisted of spindle speeds of 630 rpm, 920 rpm, and 1250 rpm, and depths of cut of 0.1 mm, 0.3 mm, and 0.5 mm, while the feed rate was maintained at 0.05 mm/rev. Vibration signals were acquired using an accelerometer connected to a PicoScope and processed in MATLAB through filtering and smoothing procedures to obtain the Root Mean Square (RMS) values. A stability map was subsequently developed to identify stable and unstable machining conditions for each combination of machining parameters. The experimental results demonstrate that the implementation of the brass passive damper effectively improves machining stability by reducing the vibration response under several machining conditions. The lowest RMS values were obtained in Variation A1 (630 rpm and 0.1 mm depth of cut), with vibration responses of 0.281 m/s² in the X-axis and 0.456 m/s² in the Y-axis, indicating the most stable machining condition. Conversely, the highest RMS values were observed in Variation A6 (920 rpm and 0.5 mm depth of cut), reaching 2.386 m/s² in the X-axis and 3.749 m/s² in the Y-axis, indicating the highest tendency for chatter occurrence. Based on the developed stability map, Variations A1, A4, A7, and A8 were identified as stable machining conditions, whereas Variations A2, A3, A5, A6, and A9 were classified as unstable. Furthermore, surface observations revealed that stable machining conditions produced smoother and more homogeneous surface finishes than unstable conditions.

Item Type:	Thesis (Other)
Uncontrolled Keywords:	Boring bar, Dynamic Vibration Absorber (DVA), Passive Damper, Getaran, Root Mean Square (RMS), Stable Zone.
Subjects:	T Technology > TJ Mechanical engineering and machinery > TJ1260 Drilling and boring.
Divisions:	Faculty of Industrial Technology > Mechanical Engineering > 21201-(S1) Undergraduate Thesis
Depositing User:	Reynaldi Dwi Cahya
Date Deposited:	28 Jul 2026 01:14
Last Modified:	28 Jul 2026 01:14
URI:	http://repository.its.ac.id/id/eprint/137982

Actions (login required)

View Item